John Murtough, the football director at Manchester United, said that Casemiro was one of the best in the world. The Brazil international was given a hero's welcome by the manager after he said he was a missing piece.
Casemiro has played less than an hour of football in the premier league. When Ten Hag picked the team to face Manchester City on Sunday, the 30-year-old was left on the bench.
The television cameras panned to the bench to show Casemiro and a former Real Madrid teammate looking bewildered as the team tore through United. It was disbelief among United supporters that one of the most experienced defensive midfielders in the world could be allowed to watch an important game from the sideline.
Explaining his decision after the 6-3 defeat, Ten Hag said he wanted to keep faith with the team which had won four league games in a row after the disastrous start to the season.
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The man said that on the day they signed him, they started to win. It is not against Casemiro that the team is doing well. Scott McTominay did a great job in the team and we got into a run. It's important for us in the long and short term. Casemiro will be in the team, but it has to come naturally.
Casemiro is likely to start for Ten Hag against Omonia FC in Cyprus on Thursday in the wake of the humiliating defeat to City. Questions remain about why a five-time winner of the European Championship is having to wait for opportunities while he is not in the first-choice XI.
Rio Ferdinand suggested that Casemiro may be regretting his decision to switch to Manchester.
Ferdinand wondered if the impact was having on someone like him. "Yes, he's experienced and whatnot, but he must be sitting there thinking, 'WOW, I'm feeling a little bit disrespected here, given what I've done,'" I would be surprised if he wasn't feeling that way.
Casemiro is thought to be Ten Hag's choice. It doesn't help that of United's five main summer signings, he is the odd one out in that he doesn't have links to either of those teams. Christian Eriksen trained with the Dutch giants while he recovered from his cardiac arrest, as well as Lisandro and Antony, both of whom played under Ten Hag.
When the proposed 85m deal with Barcelona became too complex, United turned their attention to Casemiro.
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According to sources, Ten Hag agreed to pursue Casemiro despite the fact that United managers can veto any transfer they don't agree with.
More questions have been raised about United's transfer strategy and Ten Hag is still trying to figure out what to do with his new player.
Gary Neville, a former United defender, said that every other club is very precise. Casemiro is on a contract that will cost the club over one hundred million dollars. You pay over the odds when you are desperate.
They debated if Casemiro will suit the style of play of ten Hag.
According to those close to Casemiro, his move to United was not about money, but about helping the club get back into the top European competition. For that, though, he needs to be in the team and while Ten Hag says openly that it's down to the player to prove he should be playing, Ferdinand believes his continued absence will also become an issue for the manager as well as the player.
The former England defender said that these are some of the things Ten Hag has to contend with. He has to manage that type of player, that type of ego, the pride that comes with these types of players.
If you don't play, they'll look at you differently, and that's what you have to manage. The master of the universe, Ten Hag, didn't have any issues with the players he had, he was very much in control. When you come to a top club, you have to deal with egos that are large.
Casemiro is set to get a rare chance to impress in Cyprus this week, but the real test of his status will be when Ten Hag names his team to faceEverton on Sunday.
The type of game that should suit a player with experience and composure is fast and fierce. Casemiro had to sit on the bench for most of the derby in Manchester.